Early recognition of diseases and, in particular, the prognosis of the continued course of a disease is of fundamental importance in medicine. This point especially applies to inflammatory diseases. In the case of inflammatory diseases, however, diagnosis and monitoring is complicated by the fact that these diseases are frequently accompanied by an immune reaction that affects the whole body (systemic); this results in rapid and particularly serious developments. This applies to septic diseases, which are accompanied by an above-average mortality rate.
Blood analyses can be performed to diagnose diseases. When the blood is tested, as a rule ordinary blood counts, which are quick and cheap to produce, are performed. These provide a numerical analysis of the constituents of the blood, in particular the blood cells. It is therefore possible to establish shifts in the ratio of the individual blood constituents caused by disease. Morphological cell transformations can also be determined. It is, however, a disadvantage that these quick blood tests do not permit a dynamic examination, e.g., no examination of the immunological behavior of the blood cells towards the pathogen types. For inflammatory diseases, particularly in connection with an over-activation of the immune system, a dynamic examination is of special significance. If there is septic shock, in these forms of diseases the cells of the immune system suffer a state of exhaustion known as anergy. The occurrence of anergy correlates acutely to the further fate of the patient concerned.
In a case of sepsis, the immune system reacts to the intrusion of inflammatory pathogens by a systemic immune reaction. As a consequence of the systemic immune reaction, the blood vessels dilate, thereby limiting the blood supply to the organs and impairing their function, for example, the dilatation of the blood vessels causes an undersupply of nutrients and oxygen to the brain, which can result in a septic shock. Additionally, pathogens are exported through the dilated blood vessels into the tissue and, especially, the organs. Viable, inflammatory pathogens, therefore, are to be found not only in the blood, but basically in all regions of the body, irrespective of the primary focus of infection. Damage to organs and tissue can be caused both by bacterial toxins and by activated cells of the immune system. In many cases progressive septic diseases become manifest in multiple organ failure. In Germany, for example, 250,000 to 300,000 new cases of sepsis are registered each year.
Many aspects of the complex nature of the functioning of the immune system are unknown. Uncertainty in many regards can lead to severe consequences. Well-documented clinical trial problems highlight the fact that relatively little is still known about the complex functioning of the human immune system. It is possible to treat the septic vasodilation by administering catecholamines, which cause the blood vessels to contract. If the sepsis becomes more serious, however, it is frequently associated with a catecholamine resistance. Methods for diagnosing and monitoring different subtypes of sepsis and septic shock are, and further elucidation of immune system interactions, therefore, are necessary.